Preliminary assessment of tropically weathered limestone in Sri Lanka for blastability
Document Type
Article
Publication Date
1-1-2021
Abstract
Sri Lanka is situated in a tropical climate where rainfall takes place throughout the year. As limestones in Sri Lanka are frequently exposed to rain water, limestone absorbs water and forms carbonic acid. With various geological discontinuities such as faults, folds, joints, water flows through these cavities. The weathering process along these cracks or cavities takes place at a faster rate. This further enhances the process of dissolution resulting in change in geomechanical properties of limestone. Limestone deposit at Aruwakkalu based on rock structure is classified as (i) Heavily cracked, frequent weak joints, weakly cemented layers (ii) Thin, well-cemented layers with tight joints (iii) Massive intact rock. This limestone deposit is also classified as a bedding plane dipping into the slope face, bedding plane dipping into a cut slope face and other cases. Existing system of rockmass classification at Sri Lanka is described in this paper. Thus for Aruwakkalu limestone deposit, rockmass can be classified based on type of rock structure, Blastability Index (BI), RQD, degree of weathering and degree of hardness. Average powder factor of 0.15 kg/t can be correlated with BI. © 2021, Books and Journals Private Ltd.. All rights reserved.
Keywords
Blastability index (BI), Karst, Limestone, Rock quality designation (RQD), Rock structure
Divisions
sch_civ
Funders
Management of Siam City Lanka Limited
Publication Title
Journal of Mines, Metals and Fuels
Volume
69
Issue
8
Publisher
Books and Journals Private Ltd.